A structural fire sprinkler system is composed of fire sprinkler heads that spray water into the structure interior, a series of supply pipes that deliver water under pressure from a water source to the sprinkler heads, and various types of controls for determining response parameters and starting or stopping the flow of water. Typical sprinkler heads detect a fire in the vicinity with a heat-sensitive plug that fails at a certain temperature. In a “wet” system, the water is retained under pressure in the supply pipes at the mouth of the sprinkler heads, such that the plug is the only impediment to the water being released at high velocity from the sprinkler head. Thus, upon failure of the plug, the sprinkler head is activated and immediately begins to saturate the surrounding area.
Unfortunately, typical plugs are susceptible to damage or dislocation due to unintended contact, such as bumping during a construction project, or other unwanted mechanical failure. The immediate emission of water after a plug failure is good for suppressing fires, but causes significant unnecessary water damage when a sprinkler head is simply malfunctioning. The typical response to a malfunctioning sprinkler head is to disable the entire sprinkler system, typically by turning off the system's water. However, there is usually only one valve for turning off the water, which may be far away from the malfunctioning head, hard to locate, or inaccessible without the presence of a landlord or other authorized personnel. Additionally, turning off the water leaves the building vulnerable to any actual fire that breaks out while the water is off. A device that encloses the spraying sprinkler head to limit or eliminate saturation of the surrounding area is needed. It would be advantageous for the device to be quickly and easily installed over the sprinkler head to limit water damage while allowing the fire sprinkler system to remain active. It would also be advantageous for the device to require no technical knowledge to use, so that any person who may be in the vicinity of the sprinkler head may use the device with little or no training.
The problem has been addressed with several devices that fit over the sprinkler head. One problem with known devices is that they must be held in place against the ceiling over the sprinkler head. Some devices must be physically held by a person, who is typically on a ladder, while others are held in tension using a pole that extends down to the floor under the sprinkler. The pole may not be usable if the sprinkler is installed in a high ceiling, or with no ceiling, or if furniture or other articles inhibit the path to the floor. A device that does not need to be propped against the ceiling around the sprinkler head is needed.
Another problem with known devices is that they attempt to control the flow of water by diverting it rather than stopping it. Typically, the device has an outlet that is attached to a hose or other apparatus to direct the water flowing out of the sprinkler head to a common collection area, to the sewer, or elsewhere. This is a potential waste of water and could result in water damage if there is a leak or hose damage or if the device is moved while the water is still flowing. A device that stops the flow rather than diverting it is needed.
Therefore, it is an object of this invention to provide a device to encase a spraying fire sprinkler head and prevent water damage from the spray. It is a further object that the device attach to the sprinkler head or supply pipe so it does not have to be propped against the ceiling or held in tension by the floor of the structure. A further object is to provide a device that stops the flow of water from the sprinkler head rather than diverting it. Another object of the invention is to provide a device that will stop the flow of water from a damaged sprinkler head without affecting the rest of the fire sprinkler system. Another object of the invention is to provide an easy-to-use device to encase a spraying fire sprinkler head.